In addition to this to know the "true" amount of extra calories burnt by the activity you should also subtract the RMR for the length of the activity. Example. A person has an RMR of 2400 kcal per day. That equals 2400/24=100 kcal burnt at rest (with no activity) He does exactly 1 hour of aerobic activity with an intensity that equals to 600 kcal (from the VO2 calculation) expenditure. The total amount of calorie deficit then equals to 600kcal-100 kcal=500 kcal. This is (somewhat) important since many are overly focused on calculating total calorie expenditure over a day, but forgets that even during an exercise you would still have had an RMR going on (if you were not doing the exercise) so you shouldn't say that you burnt an extra 600 kcal. It is the calorie deficit that most people ("over-focusing") on the numbers from the machines is aiming for. For some people to feel "Wow I have burn this many calories. Now I can afford this or that junk food as a reward! This is even more evident for people doing very low intensity workouts, like walking on a treadmill where the difference in doing that compared to the RMR is even less. If they try to calculate the daily calorie expenditure they shouldn't add 600 kcal (As in the example) to the calorie expenditure daily total with that activity but 500 kcal, to in the end know what the total calorie deficit (if that is what they are aiming for) for the day will be. In addition to this, the machines you are doing the exercise on won't take into account how efficient the person doing the exercise is. People use different techniques, have different limb lengths etc and the assumed calculated number (from body weight and somehow watts expenditure on the machine) is only an average. This is especially important for running on treadmills where the difference in running economy between a beginner and an advanced runner is huge. One of the main differences between the beginner and the advanced runner (besides VO2 max, lactate threshold etc) is that the advanced runner expends much, much LESS calories for every time unit per kg bodyweight at the same running speed (ie every "Watt" costs much less for the advanced runner to overcome so they are able to run faster at the same fatigue level even if they would have had the same VO2 max.). The number would differ much less on a spinning bike or a crosstrainer. It is very hard for people to calculate the calorie intake to any level of precision anyway so I think this is more of a theoretical exercise! :)
I have a problem that asks me to find the calorie expenditure per minute from a person weighing 70 kg, and working with a load of 150 watts. How would I go about doing that?
@@VivoPhys Hi Dr. Evans, I just graduated from my B.S in Ex Science, and I am taking the ACSM Exercise Physiologist exam in 2-3 weeks, what would you recommend for me to study? I am currently taking a look at all your videos, and most if not all of them are related to the content in the ACSM EP Guidelines book, but I'd appreciate if you could give me a little insight, thank you.
This book is designed to help with that exam. ACSM's Resources for the Exercise Physiologist (American College of Sports Medicine) www.amazon.com/dp/1975153162/ref=cm_sw_r_awdo_navT_g_KCZ8B6Z15817MDWVCVCJ
You're the man. Thanks for helping with my studies!
I'm glad it helped.
In addition to this to know the "true" amount of extra calories burnt by the activity you should also subtract the RMR for the length of the activity.
Example. A person has an RMR of 2400 kcal per day.
That equals 2400/24=100 kcal burnt at rest (with no activity)
He does exactly 1 hour of aerobic activity with an intensity that equals to 600 kcal (from the VO2 calculation) expenditure.
The total amount of calorie deficit then equals to 600kcal-100 kcal=500 kcal. This is (somewhat) important since many are overly focused on calculating total calorie expenditure over a day, but forgets that even during an exercise you would still have had an RMR going on (if you were not doing the exercise) so you shouldn't say that you burnt an extra 600 kcal. It is the calorie deficit that most people ("over-focusing") on the numbers from the machines is aiming for. For some people to feel "Wow I have burn this many calories. Now I can afford this or that junk food as a reward!
This is even more evident for people doing very low intensity workouts, like walking on a treadmill where the difference in doing that compared to the RMR is even less. If they try to calculate the daily calorie expenditure they shouldn't add 600 kcal (As in the example) to the calorie expenditure daily total with that activity but 500 kcal, to in the end know what the total calorie deficit (if that is what they are aiming for) for the day will be.
In addition to this, the machines you are doing the exercise on won't take into account how efficient the person doing the exercise is. People use different techniques, have different limb lengths etc and the assumed calculated number (from body weight and somehow watts expenditure on the machine) is only an average.
This is especially important for running on treadmills where the difference in running economy between a beginner and an advanced runner is huge. One of the main differences between the beginner and the advanced runner (besides VO2 max, lactate threshold etc) is that the advanced runner expends much, much LESS calories for every time unit per kg bodyweight at the same running speed (ie every "Watt" costs much less for the advanced runner to overcome so they are able to run faster at the same fatigue level even if they would have had the same VO2 max.).
The number would differ much less on a spinning bike or a crosstrainer.
It is very hard for people to calculate the calorie intake to any level of precision anyway so I think this is more of a theoretical exercise! :)
All good points. Thanks for commenting this.
I have a problem that asks me to find the calorie expenditure per minute from a person weighing 70 kg, and working with a load of 150 watts. How would I go about doing that?
Awesome video. Can this be used to estimate calorie use in non-maximal exercises as well? So VO2 Max is not necessary for this formula to work right?
If you know the submaximal VO2 you can use this method with that.
@@VivoPhys yes I can measure that like you measured it for Hamed. In fact I want an actual steady VO2 as opposed to maximum exertion. Thanks
Thank you!
You are welcome!
@@VivoPhys Hi Dr. Evans, I just graduated from my B.S in Ex Science, and I am taking the ACSM Exercise Physiologist exam in 2-3 weeks, what would you recommend for me to study? I am currently taking a look at all your videos, and most if not all of them are related to the content in the ACSM EP Guidelines book, but I'd appreciate if you could give me a little insight, thank you.
This book is designed to help with that exam.
ACSM's Resources for the Exercise Physiologist (American College of Sports Medicine) www.amazon.com/dp/1975153162/ref=cm_sw_r_awdo_navT_g_KCZ8B6Z15817MDWVCVCJ
I was wondering how do you convert oxygen in ml/min to ml/kg/min
Just divide the ml/min by body mass in kg.
Can someone tell me where that 5 came from while calculating calories?
It is the approximate number of calories consumed per liter of oxygen consumed during aerobic metabolism.
@@VivoPhys thank you so much Dr. Matthews
5 mins is work time